I think she might think Matt and Dom are US citizens, because they live here, but they aren't.
Matt confirmed he doesn't even have dual citizenship, and can't vote in the US. And he voted in the UK on Brexit/Bremain.

And Americans care about Brexit not only because it does impact the global economy, but because we're not all the sheltered, xenophobic bastards we get portrayed as, and we actually care about what's going on around the planet, and it's slide into backwards politics and hate.

Yeah if the US late night shows are anything to demonstrate, there were a lot of people in the US who had an interest in Brexit. Not least given it had a huge ripple on the stock market when it happened.